190 



Length of the specimen 9 lines ; width at the body whorl 7 lines, 

 the shape of 31. hellioincta, but is smaller and not so acute. 



Haa 



Locality and Formation.- 

 group. 



Collector. — J. Richardson. 



-Point Ldvis ; in limestone No. 2, Quebec 



MuRCHisoNiA Sylvia. (N. sp.) 



Description. — Apical angle .about 80° ; whorls four, strongly ventricose, 

 with a median band which forms on the cast of the interior an obscure 

 rounded angulation. Surface of the cast with narrow, faint grooves cross- 

 ing from the suture backwards to the band, and then forwards. 



Length of largest specimen 10 hues ; width at the body whorl about 

 the same. 



Diifers from M. Cassandra in being proportionally shorter and more 

 oblique. 



Locality and Formation. — Point L^vis ; in limestone No. 2, Quebec 

 group. 



Collectors. — J. Richardson, R. Bell, T. C. Weston. 



Pleueotomaria Quebecexsis. (N. sp.) 



Fig. 172. 



Fig. lYS. 



Fig. 174. 



Figs. ll2-\1i.— Pleurotomaria Quebecensis. Pig. 174. A polished section through 

 a specimen, showing the wide umbilicus, a, magnified view of the margin of 

 the body-whorl. 



Description. — Shell pyramidal, varying in height, consisting of jSve or 

 six slender whorls. The whorls are usually nearly flat on the upper side, 

 the surface forming a straight slope from the acute apex to the angular 

 margin of the body-whorl ; sometimes gently convex with a tendency to 

 become slightly concave in the loAver half. On the under side the most 

 convex part of the whorl is close to the umbilicus, the edge of which is 

 obtusely rounded angular. From the margin to the umbilicus the whorls 

 are depressed convex. The margin of the body-whorl is somewhat 

 acutely angular, narrowly rounded. The umbilicus is wide, being at 



